#include <iostream>

using std::cout;
using std::endl;

class A
{
public:
    void print() const
    {   cout << "A::print()" << endl;   }
};


class B
{
public:
    void display() const
    {   cout << "B::display()" << endl;   }
};

class C
{
public:
    void show() const
    {   cout << "C::show()" << endl;   }
};

class D
: public A
//, B    //默认继承方式 private
, public B
, public C
{};

int main()
{
    D d;
    d.print();
    d.display();
    d.show();

    return 0;
}

